Ipomoea batatas is a member of the morning glory family Convolvulaceae. This species is grown worldwide and it exhibits a wide range of plant forms and colors. The cultivated members of Ipomoea batatas grown by farmers worldwide are commonly produced for consumption of their nutritious, enlarged storage roots. These types typically produce a fast growing green vine that has a wide variety of leaf shapes ranging from palmate and deeply lobed, to cordate or triangular shaped leaves with no lobes.
Like their edible forms, Ipomoea batatas ornamental sweetpotato (OSP) plants are a heat-loving, drought-tolerant, perennial vine typically grown as an annual. However, ornamental sweetpotato plants are distinguished from the edible cultivated forms in that they possess unique foliage colors, leaf shapes, and growth habits, giving them significant value in the ornamental marketplace.
Ornamental sweetpotatoes are desirable in the landscape and ornamental industries because their foliage comes in a wide variety of colors (e.g. pale yellow to dark purple with some exhibiting temporal and individual leaf color variegation patterns) and plant shapes (e.g. mounded and very compact to prostrate and highly spreading). They can be grown in a potted plant and/or mixed planting format, and they have the ability to cover a large space or hang over walls and decorative pots creating brightly colored and textured backdrops in gardens and patios. Most ornamental sweetpotatoes continue to grow throughout the entire growing season and require little maintenance. Moreover, these plants have few insect or disease problems.
To meet the growing horticultural demand for ornamental sweetpotatoes, it is desirable to produce new cultivars of ornamental sweetpotato with new or improved foliage colors, variegation patterns, leaf shapes, and plant architectures. In addition, it would be advantageous to develop cultivars of ornamental sweetpotato exhibiting a more compact growth habit that do not out-compete other species in mixed containers.
‘NCORNSP-021SHJB’ was bred to meet the increasing demand for new ornamental sweetpotatoes. ‘NCORNSP-021SHJB’ is a moderately compact, to compact, non-twining, slightly upright variety producing many short shoots. It is distinguishable from other ornamental sweetpotato cultivars by its purple heart-shaped leaves that are entire with a cordate base; a moderately compact, to compact habit and semi-erect mounding plant architecture. The purple leaves of this plant, short internodes, and the plant architecture are what make ‘NCORNSP-021SHJB’ unique amongst the current ornamental sweetpotatoes in the marketplace. ‘NCORNSP-021SHJB’ also exhibits very good vigor and is very well branched. In greenhouse and field trials conducted since 2013, ‘NCORNSP-021SHJB’ has been shown to be much less vigorous than the Ipomoea batatas OSP ‘Margarita’ and ‘Blackie’ and is suitable for use as a landscape or containerized plant. The production of flowers by ‘NCORNSP-021SHJB’ sporadic under short day conditions.
Lineage. ‘NCORNSP-021SHJB’ (breeding designation NC8219-006ORN) originated from open pollinated seed harvest from the proprietary Ipomoea batatas breeding line NC6751-045ORN (the female parent; not patented). Botanical seed was harvested from this and other ornamental sweetpotato lines planted in our summer advanced ornamental replicated trials between June of 2012 and November of 2012 in Clinton, N.C. NC6751-045ORN resulted from a conventional cross between the proprietary Ipomoea batatas breeding lines NC4855-001ORN (the female parent; not patented) and ‘Sweet Caroline Sweetheart Red’ (the male parent; U.S. Plant Pat. No. 19,013). Botanical seed from this half-sib family was planted in the greenhouse in December 2012. The first cycle of selection on the population was exercised in the seedling trays and survivors were transferred to a single 6-inch pot, which was then maintained in the greenhouse. Cuttings (2 each) were taken from the plants in April and planted in the field as 2-plant unreplicated plots during mid-June 2013. The single, individual plant now known as ‘NCORNSP-021SHJB’ was selected Sep. 6, 2013 based on its combination of exceptional features, and has been propagated asexually since that time.
Asexual Reproduction. Since its selection, Ipomoea batatas ‘NCORNSP-021SHJB’ has been asexually reproduced in North Carolina predominantly by vegetative propagation of vine cuttings. Successively, there have been four cycles of vegetative propagation, one cycle of tissue culture micropropagation, and multiple vegetative propagation cycles to increase the plant population. Asexual reproduction of ‘NCORNSP-021SHJB’ by cuttings has shown that the unique features of the new cultivar are stable and the plant reproduces true to type in successive generations.